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Type: Reptile

Diet: Carnivore

Average life span in the wild: 20 to 30 years Size:20 in (50 cm)

Weight:4 lbs (1.8 kg)

Group name: Lounge

Protection status: Threatened

Habitat: Desert and semiarid regions of gravelly and sandy soils with shrubs. Found under rocks, in burrows of other animals and in holes it digs itself.

The Gila monster is one of only a handful of venomous lizards in the world. Others include the similar-looking Mexican beaded lizards, as well as iguanas and monitor lizards. Its venom is a fairly mild neurotoxin. And though a Gila bite is extremely painful, none has resulted in a reported human death. Unlike snakes, which inject venom, Gilas latch onto victims and chew to allow neurotoxins to move through grooves in their teeth and into the open wound.

Gilas are lethargic creatures that feed primarily on eggs raided from nests and newborn mammals. They may spend more than 95 percent of their lives in underground burrows, emerging only to feed and occasionally to bask in the desert sun. They can store fat in their oversized tails and are able to go months between meals.

Gila populations are shrinking due primarily to human encroachment, and they are considered a threatened species.

Found mainly in the Mojave, Sonoran and Chihuahuan deserts of extreme southwestern Utah, southern Nevada, southeastern California, Arizona and southwestern New Mexico into Mexico.

During warm weather the Gila Monster feeds at night on small mammals, birds and eggs. Fat stored in the tail and abdomen during this period is utilized during the winter months. Both species of Heloderma are sluggish in habit, but they have a strong, tenacious bite.

Gila Monster

Life Cycle
Gila Monsters mate throughout the summer months, with the female laying 3 to 5 eggs in sandy soils, burrows or under rocks, during fall or winter.
The Gila Monster is a stout-bodied lizard that grows 18 to 24 inches in length. It has black, orange, pink or yellow broken blotches, bars and spots, with bands extending onto its blunt tail. Its face is black, and it has small, bead-like scales across its back. It is named for the Gila River Basin of the southwestern United States.

The Gila Monster is one of only two species of venomous lizards; both are of the family Helodermatidae and both are similar in appearance and habits. Its venomous cousin, the Mexican Beaded Lizard (Heloderma horridum), is slightly larger and darker.

Most of the Gila Monster's teeth have two grooves that conduct the venom, a nerve toxin, from glands in the lower jaw. The toxin is not injected like that of the snake, but flows into the wound as the lizard chews on its victim. While the bite can overpower predators and prey, it is rarely fatal to humans.

There are 2 subspecies of Gila Monsters in the deserts of the Southwest:

H.s. suspectum (Reticulate) resides primarily in the Sonoran and Chihuahuan deserts. Adults are mottled and blotched.

H.s. cinctum (Banded) resides primarily in the Mojave Desert. Adults have a broad double crossband.
Gila Monsters are one of only two species of seriously venomous lizards!